This book explores the character of the Eucharist as communion in and through sacrifice.Drawing on Jewish reflection upon the Aqedah (the near-sacrifice of Isaac by Abraham in Genesis), as well as on other critical analyses of sacrifice in Scripture, the book shows that communion is not possible without the reconciliation attained by sacrificial self-giving love. Following the insights of St Thomas Aquinas, the author argues that all aspects of Eucharistic theology, including metaphysical doctrines such as transubstantiation, depend upon recognizing that communion cannot be separated from its sacrificial context.The book will stimulate discussion because of its controversial critique of the dominant paradigm for Eucharistic theology, its reclamation of St Thomas Aquinas 's theology of the Eucharist, and its response to Pope John Paul II 's Ecclesia de Eucharistia.